Antonio Vargas - Academia.edu (original) (raw)

Papers by Antonio Vargas

International Journal of Molecular Sciences

Maternal malnutrition in critical periods of development increases the risk of developing short- ... more Maternal malnutrition in critical periods of development increases the risk of developing short- and long-term diseases in the offspring. The alterations induced by this nutritional programming in the hypothalamus of the offspring are of special relevance due to its role in energy homeostasis, especially in the endocannabinoid system (ECS), which is involved in metabolic functions. Since astrocytes are essential for neuronal energy efficiency and are implicated in brain endocannabinoid signaling, here we have used a rat model to investigate whether a moderate caloric restriction (R) spanning from two weeks prior to the start of gestation to its end induced changes in offspring hypothalamic (a) ECS, (b) lipid metabolism (LM) and/or (c) hypothalamic astrocytes. Monitorization was performed by analyzing both the gene and protein expression of proteins involved in LM and ECS signaling. Offspring born from caloric-restricted mothers presented hypothalamic alterations in both the main enz...

Mathematics

We introduce a meshless method derived by considering the time variable as a spatial variable wit... more We introduce a meshless method derived by considering the time variable as a spatial variable without the need to extend further conditions to the solution of linear and non-linear parabolic PDEs. The method is based on a moving least squares method, more precisely, the generalized finite difference method (GFDM), which allows us to select well-conditioned stars. Several 2D and 3D examples, including the time variable, are shown for both regular and irregular node distributions. The results are compared with explicit GFDM both in terms of errors and execution time.

Mathematics, 2021

The existence and uniqueness of the discrete solutions of a porous medium equation with diffusion... more The existence and uniqueness of the discrete solutions of a porous medium equation with diffusion are demonstrated. The Cauchy problem contains a fractional Laplacian and it is equivalent to the extension formulation in the sense of trace and harmonic extension operators. By using the generalized finite difference method, we obtain the convergence of the numerical solution to the classical/theoretical solution of the equation for nonnegative initial data sufficiently smooth and bounded. This procedure allows us to use meshes with complicated geometry (more realistic) or with an irregular distribution of nodes (providing more accurate solutions where needed). Some numerical results are presented in arbitrary irregular meshes to illustrate the potential of the method.

Mathematics, 2022

The applications of the Eikonal and stationary heat transfer equations in broad fields of science... more The applications of the Eikonal and stationary heat transfer equations in broad fields of science and engineering are the motivation to present an implementation, not only valid for structured domains but also for completely irregular domains, of the meshless Generalized Finite Difference Method (GFDM). In this paper, the fully non-linear Eikonal equation and the stationary heat transfer equation with variable thermal conductivity and source term are solved in 2D. The explicit formulae for derivatives are developed and applied to the equations in order to obtain the numerical schemes to be used. Moreover, the numerical values that approximate the functions for the considered domain are obtained. Numerous examples for both equations on irregular 2D domains are exposed to underline the effectiveness and practicality of the method.

Mathematics, 2022

We consider a system of two differential equations modeling chemotaxis. The system consists of a ... more We consider a system of two differential equations modeling chemotaxis. The system consists of a parabolic equation describing the behavior of a biological species “u” coupled to an ODE patterning the concentration of a chemical substance “v”. The growth of the biological species is limited by a logistic-like term where the carrying capacity presents a time-periodic asymptotic behavior. The production of the chemical species is described in terms of a regular function h, which increases as “u” increases. Under suitable assumptions we prove that the solution is globally bounded in time by using an Alikakos-Moser iteration, and it fulfills a certain periodic asymptotic behavior. Besides, numerical simulations are performed to illustrate the behavior of the solutions of the system showing that the model considered here can provide very interesting and complex dynamics.

Nutrients, 2021

Obesity is currently a major epidemic in the developed world. However, we lack a wide range of ef... more Obesity is currently a major epidemic in the developed world. However, we lack a wide range of effective pharmacological treatments and therapies against obesity, and those approved are not devoid of adverse effects. Dietary components such as palmitoleic acid have been proposed to improve metabolic disbalance in obesity, although the mechanisms involved are not well understood. Both palmitoleic acid (POA) and oleic acid (OA) can be transformed in N-acylethanolamines (NAEs), mediating the effects of dietary POA and OA. To test this hypothesis, here, we study the effects on food intake and body weight gain of palmitoleylethanolamide (POEA) and the OA-derived NAE analogue, oleoylethanolamide (OEA), in Sprague–Dawley rats with a hypercaloric cafeteria diet (HFD). Plasma biochemical metabolites, inflammatory mediators, and lipogenesis-associated liver protein expression were also measured. The results indicate that POEA is able to improve health status in diet-induced obesity, decreasin...

Mathematics, 2021

In this paper, we show the application of the meshless numerical method called “Generalized Finit... more In this paper, we show the application of the meshless numerical method called “Generalized Finite Diference Method” (GFDM) for solving a model for tumor growth with nutrient density, extracellular matrix and matrix degrading enzymes, [recently proposed by Li and Hu]. We derive the discretization of the parabolic–hyperbolic–parabolic–elliptic system by means of the explicit formulae of the GFDM. We provide a theoretical proof of the convergence of the spatial–temporal scheme to the continuous solution and we show several examples over regular and irregular distribution of points. This shows the feasibility of the method for solving this nonlinear model appearing in Biology and Medicine in complicated and realistic domains.

Unemployment and precariousness are one of the major determinants of poverty in Spain and have be... more Unemployment and precariousness are one of the major determinants of poverty in Spain and have been aggravated by the economic crisis of the last decade. The lack of resources threatens the food security of families who are forced to adopt purchasing strategies that lead to a reduction in the consumption of fresh food and an increase in refined and ultraprocessed products. These high-calorie, low-nutritional value diets, coupled with sedentary lifestyles, lead to a double burden of malnutrition where obesity and micronutrient deficiencies coexist. Nutritional status largely determines the physical and mental health of individuals but this relationship is not direct and unidirectional. All of the above factors feed off each other and are in turn crossed by other transversal elements such as energy poverty, globalization, gender inequality or access to education and health services, among others. Multisectoral interventions such as integral social-labour insertion itineraries and coll...

In this paper we debate the intentionality of designers and developers in their videogames propos... more In this paper we debate the intentionality of designers and developers in their videogames propositions. We start by presenting the concept of artistic intentionality (based on Heidegger), which, by definition, includes the affirmation and negation of the tradition of Art (Gadamer). Then, we extend the discussion to the being-game, presenting definitions of what is videogame (Salen and Zimmerman; Juul; Aarseth and Calleja) and argue that videogames must be designed as a game and a non-game simultaneously, because this is necessary to renew and consolidate this young tradition. That discussion is based on historical debates – as about indie vs. mainstream games (Ferreira; Jahn-Sudmann; Flanagan) and the Scratchware Manifesto – making a connection between Videogames and Art.

Over 90 recipes to empower you to configure, integrate, and manage your very own Lync Server depl... more Over 90 recipes to empower you to configure, integrate, and manage your very own Lync Server deployment About This BookCustomize and manage Lync security and authentication on cloud and mobileDiscover the best ways to integrate Lync with Exchange and explore resource forestsThe book is designed to teach you how to select the best tools, debugging methods, and monitoring options to help you in your day-to-day workWho This Book Is ForIf you work with Lync on a daily basis or if you have to use a specific feature of Lync for a project, this is the book for you. For solutions architects, technical consultants, and administrators, if you have a Lync deployment and you want to upgrade, integrate, secure, or extend it to the cloud, you can get valuable information from the recipes in this book. In Detail This book begins with the fundamental security-related tasks you should be aware of when working with Lync, before moving on to walk you through the authentication mechanisms. You will get...

International Journal of Molecular Sciences, 2021

Deficiency of pregnancy-associated plasma protein-A2 (PAPP-A2), an IGF-1 availability regulator, ... more Deficiency of pregnancy-associated plasma protein-A2 (PAPP-A2), an IGF-1 availability regulator, causes postnatal growth failure and dysregulation of bone size and density. The present study aimed to determine the effects of recombinant murine IGF-1 (rmIGF-1) on bone composition and remodeling in constitutive Pappa2 knock-out (ko/ko) mice. To address this challenge, X-ray diffraction (XRD), attenuated total reflection-fourier transform infra-red (ATR-FTIR) spectroscopy and gene expression analysis of members of the IGF-1 system and bone resorption/formation were performed. Pappa2ko/ko mice (both sexes) had reduced body and bone length. Male Pappa2ko/ko mice had specific alterations in bone composition (mineral-to-matrix ratio, carbonate substitution and mineral crystallinity), but not in bone remodeling. In contrast, decreases in collagen maturity and increases in Igfbp3, osteopontin (resorption) and osteocalcin (formation) characterized the bone of Pappa2ko/ko females. A single rmI...

Journal of Comparative Neurology, 2020

Adult neurogenesis in rodents is modulated by dopaminergic signaling and inhibited by cocaine. Ho... more Adult neurogenesis in rodents is modulated by dopaminergic signaling and inhibited by cocaine. However, the sex‐specific role of dopamine D1 and D2 receptors (D1R, D2R) in the deleterious effect of cocaine on adult neurogenesis has not been described yet. Here, we explored sex differences in (a) cell proliferation (5′‐bromo‐2′‐deoxyuridine [BrdU]), (b) neural precursor (nestin), (c) neuronal phenotype (BrdU/β3‐tubulin), and (d) neuronal maturity (NeuN) in the subventricular zone (SVZ) of the lateral ventricles and striatum of mice with genetic deletion (D1−/−, D2−/−) or pharmacological blockage (SCH23390: 0.1 mg/kg/day/5 days; Raclopride: 0.3 mg/kg/day/5 days) of D1R and D2R, and treated (10 mg/kg/day/5 days) and then challenged (5 mg/kg, 48 hr later) with cocaine. Results indicated that hyperactivity responses to cocaine were absent in D1−/− mice and reduced in SCH23390‐treated mice. Activity responses to cocaine were reduced in D2−/− males, but absent in D2−/− females and increased in Raclopride‐treated females. D1R deletion blocked the deleterious effect of cocaine on SVZ cell proliferation in males. Cocaine‐exposed D1−/− males also had reduced neuronal phenotype of SVZ newborn cells and increased striatal neuronal maturity. D2−/− mice had lower proliferative and neural precursor responses. Cocaine in D2−/− females or coadministered with Raclopride in wild‐type females improved SVZ cell proliferation, an effect that positively correlated with plasma brain‐derived neurotrophic factor (BDNF) concentrations. In conclusion, the sex‐specific D1R and D2R signaling on SVZ cell proliferation, neural progenitor and neuronal maturity is differentially perturbed by cocaine, and BDNF may be required to link D2R to neuroplasticity in cocaine addiction in females.

Time’s Causal Power, 2021

Nutrients, 2021

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Mathematics, 2020

In this paper we obtain a novel implementation for irregular clouds of nodes of the meshless meth... more In this paper we obtain a novel implementation for irregular clouds of nodes of the meshless method called Generalized Finite Difference Method for solving the complex Ginzburg–Landau equation. We derive the explicit formulae for the spatial derivative and an explicit scheme by splitting the equation into a system of two parabolic PDEs. We prove the conditional convergence of the numerical scheme towards the continuous solution under certain assumptions. We obtain a second order approximation as it is clear from the numerical results. Finally, we provide several examples of its application over irregular domains in order to test the accuracy of the explicit scheme, as well as comparison with other numerical methods.

Palíndromo, 2013

Os games (jogos eletrônicos) são fenômeno marcante nos valores e hábitos da cultura atual, eviden... more Os games (jogos eletrônicos) são fenômeno marcante nos valores e hábitos da cultura atual, evidenciando a importância do jogo para a humanidade. Eles são objeto de fundamentação interdisciplinar, demandam diálogo entre profissionais de áreas diversas. Por isso, o projeto “Diálogos entre Arte e Design” (UDESC/CNPq, 2012-2013) foi proposto por seis pesquisadores de games educativos e/ou artísticos. O diálogo é norteado pelo game A mansão de Quelícera, resultado e objeto de pesquisas acadêmicas que tanto destacaram as qualidades do jogo quanto apontaram melhorias possíveis. Este artigo apresenta o ponto de partida do “Diálogos entre Arte e Design”, o qual tem por objetivo: a) aproximar conceitos e métodos usados no desenvolvimento e na avaliação de games educativos; b) produzir versão revisada de A mansão de Quelícera, a ser disponibilizada gratuitamente na web a partir de 2013.

International Journal of Molecular Sciences

Maternal malnutrition in critical periods of development increases the risk of developing short- ... more Maternal malnutrition in critical periods of development increases the risk of developing short- and long-term diseases in the offspring. The alterations induced by this nutritional programming in the hypothalamus of the offspring are of special relevance due to its role in energy homeostasis, especially in the endocannabinoid system (ECS), which is involved in metabolic functions. Since astrocytes are essential for neuronal energy efficiency and are implicated in brain endocannabinoid signaling, here we have used a rat model to investigate whether a moderate caloric restriction (R) spanning from two weeks prior to the start of gestation to its end induced changes in offspring hypothalamic (a) ECS, (b) lipid metabolism (LM) and/or (c) hypothalamic astrocytes. Monitorization was performed by analyzing both the gene and protein expression of proteins involved in LM and ECS signaling. Offspring born from caloric-restricted mothers presented hypothalamic alterations in both the main enz...

Mathematics

We introduce a meshless method derived by considering the time variable as a spatial variable wit... more We introduce a meshless method derived by considering the time variable as a spatial variable without the need to extend further conditions to the solution of linear and non-linear parabolic PDEs. The method is based on a moving least squares method, more precisely, the generalized finite difference method (GFDM), which allows us to select well-conditioned stars. Several 2D and 3D examples, including the time variable, are shown for both regular and irregular node distributions. The results are compared with explicit GFDM both in terms of errors and execution time.

Mathematics, 2021

The existence and uniqueness of the discrete solutions of a porous medium equation with diffusion... more The existence and uniqueness of the discrete solutions of a porous medium equation with diffusion are demonstrated. The Cauchy problem contains a fractional Laplacian and it is equivalent to the extension formulation in the sense of trace and harmonic extension operators. By using the generalized finite difference method, we obtain the convergence of the numerical solution to the classical/theoretical solution of the equation for nonnegative initial data sufficiently smooth and bounded. This procedure allows us to use meshes with complicated geometry (more realistic) or with an irregular distribution of nodes (providing more accurate solutions where needed). Some numerical results are presented in arbitrary irregular meshes to illustrate the potential of the method.

Mathematics, 2022

The applications of the Eikonal and stationary heat transfer equations in broad fields of science... more The applications of the Eikonal and stationary heat transfer equations in broad fields of science and engineering are the motivation to present an implementation, not only valid for structured domains but also for completely irregular domains, of the meshless Generalized Finite Difference Method (GFDM). In this paper, the fully non-linear Eikonal equation and the stationary heat transfer equation with variable thermal conductivity and source term are solved in 2D. The explicit formulae for derivatives are developed and applied to the equations in order to obtain the numerical schemes to be used. Moreover, the numerical values that approximate the functions for the considered domain are obtained. Numerous examples for both equations on irregular 2D domains are exposed to underline the effectiveness and practicality of the method.

Mathematics, 2022

We consider a system of two differential equations modeling chemotaxis. The system consists of a ... more We consider a system of two differential equations modeling chemotaxis. The system consists of a parabolic equation describing the behavior of a biological species “u” coupled to an ODE patterning the concentration of a chemical substance “v”. The growth of the biological species is limited by a logistic-like term where the carrying capacity presents a time-periodic asymptotic behavior. The production of the chemical species is described in terms of a regular function h, which increases as “u” increases. Under suitable assumptions we prove that the solution is globally bounded in time by using an Alikakos-Moser iteration, and it fulfills a certain periodic asymptotic behavior. Besides, numerical simulations are performed to illustrate the behavior of the solutions of the system showing that the model considered here can provide very interesting and complex dynamics.

Nutrients, 2021

Obesity is currently a major epidemic in the developed world. However, we lack a wide range of ef... more Obesity is currently a major epidemic in the developed world. However, we lack a wide range of effective pharmacological treatments and therapies against obesity, and those approved are not devoid of adverse effects. Dietary components such as palmitoleic acid have been proposed to improve metabolic disbalance in obesity, although the mechanisms involved are not well understood. Both palmitoleic acid (POA) and oleic acid (OA) can be transformed in N-acylethanolamines (NAEs), mediating the effects of dietary POA and OA. To test this hypothesis, here, we study the effects on food intake and body weight gain of palmitoleylethanolamide (POEA) and the OA-derived NAE analogue, oleoylethanolamide (OEA), in Sprague–Dawley rats with a hypercaloric cafeteria diet (HFD). Plasma biochemical metabolites, inflammatory mediators, and lipogenesis-associated liver protein expression were also measured. The results indicate that POEA is able to improve health status in diet-induced obesity, decreasin...

Mathematics, 2021

In this paper, we show the application of the meshless numerical method called “Generalized Finit... more In this paper, we show the application of the meshless numerical method called “Generalized Finite Diference Method” (GFDM) for solving a model for tumor growth with nutrient density, extracellular matrix and matrix degrading enzymes, [recently proposed by Li and Hu]. We derive the discretization of the parabolic–hyperbolic–parabolic–elliptic system by means of the explicit formulae of the GFDM. We provide a theoretical proof of the convergence of the spatial–temporal scheme to the continuous solution and we show several examples over regular and irregular distribution of points. This shows the feasibility of the method for solving this nonlinear model appearing in Biology and Medicine in complicated and realistic domains.

Unemployment and precariousness are one of the major determinants of poverty in Spain and have be... more Unemployment and precariousness are one of the major determinants of poverty in Spain and have been aggravated by the economic crisis of the last decade. The lack of resources threatens the food security of families who are forced to adopt purchasing strategies that lead to a reduction in the consumption of fresh food and an increase in refined and ultraprocessed products. These high-calorie, low-nutritional value diets, coupled with sedentary lifestyles, lead to a double burden of malnutrition where obesity and micronutrient deficiencies coexist. Nutritional status largely determines the physical and mental health of individuals but this relationship is not direct and unidirectional. All of the above factors feed off each other and are in turn crossed by other transversal elements such as energy poverty, globalization, gender inequality or access to education and health services, among others. Multisectoral interventions such as integral social-labour insertion itineraries and coll...

In this paper we debate the intentionality of designers and developers in their videogames propos... more In this paper we debate the intentionality of designers and developers in their videogames propositions. We start by presenting the concept of artistic intentionality (based on Heidegger), which, by definition, includes the affirmation and negation of the tradition of Art (Gadamer). Then, we extend the discussion to the being-game, presenting definitions of what is videogame (Salen and Zimmerman; Juul; Aarseth and Calleja) and argue that videogames must be designed as a game and a non-game simultaneously, because this is necessary to renew and consolidate this young tradition. That discussion is based on historical debates – as about indie vs. mainstream games (Ferreira; Jahn-Sudmann; Flanagan) and the Scratchware Manifesto – making a connection between Videogames and Art.

Over 90 recipes to empower you to configure, integrate, and manage your very own Lync Server depl... more Over 90 recipes to empower you to configure, integrate, and manage your very own Lync Server deployment About This BookCustomize and manage Lync security and authentication on cloud and mobileDiscover the best ways to integrate Lync with Exchange and explore resource forestsThe book is designed to teach you how to select the best tools, debugging methods, and monitoring options to help you in your day-to-day workWho This Book Is ForIf you work with Lync on a daily basis or if you have to use a specific feature of Lync for a project, this is the book for you. For solutions architects, technical consultants, and administrators, if you have a Lync deployment and you want to upgrade, integrate, secure, or extend it to the cloud, you can get valuable information from the recipes in this book. In Detail This book begins with the fundamental security-related tasks you should be aware of when working with Lync, before moving on to walk you through the authentication mechanisms. You will get...

International Journal of Molecular Sciences, 2021

Deficiency of pregnancy-associated plasma protein-A2 (PAPP-A2), an IGF-1 availability regulator, ... more Deficiency of pregnancy-associated plasma protein-A2 (PAPP-A2), an IGF-1 availability regulator, causes postnatal growth failure and dysregulation of bone size and density. The present study aimed to determine the effects of recombinant murine IGF-1 (rmIGF-1) on bone composition and remodeling in constitutive Pappa2 knock-out (ko/ko) mice. To address this challenge, X-ray diffraction (XRD), attenuated total reflection-fourier transform infra-red (ATR-FTIR) spectroscopy and gene expression analysis of members of the IGF-1 system and bone resorption/formation were performed. Pappa2ko/ko mice (both sexes) had reduced body and bone length. Male Pappa2ko/ko mice had specific alterations in bone composition (mineral-to-matrix ratio, carbonate substitution and mineral crystallinity), but not in bone remodeling. In contrast, decreases in collagen maturity and increases in Igfbp3, osteopontin (resorption) and osteocalcin (formation) characterized the bone of Pappa2ko/ko females. A single rmI...

Journal of Comparative Neurology, 2020

Adult neurogenesis in rodents is modulated by dopaminergic signaling and inhibited by cocaine. Ho... more Adult neurogenesis in rodents is modulated by dopaminergic signaling and inhibited by cocaine. However, the sex‐specific role of dopamine D1 and D2 receptors (D1R, D2R) in the deleterious effect of cocaine on adult neurogenesis has not been described yet. Here, we explored sex differences in (a) cell proliferation (5′‐bromo‐2′‐deoxyuridine [BrdU]), (b) neural precursor (nestin), (c) neuronal phenotype (BrdU/β3‐tubulin), and (d) neuronal maturity (NeuN) in the subventricular zone (SVZ) of the lateral ventricles and striatum of mice with genetic deletion (D1−/−, D2−/−) or pharmacological blockage (SCH23390: 0.1 mg/kg/day/5 days; Raclopride: 0.3 mg/kg/day/5 days) of D1R and D2R, and treated (10 mg/kg/day/5 days) and then challenged (5 mg/kg, 48 hr later) with cocaine. Results indicated that hyperactivity responses to cocaine were absent in D1−/− mice and reduced in SCH23390‐treated mice. Activity responses to cocaine were reduced in D2−/− males, but absent in D2−/− females and increased in Raclopride‐treated females. D1R deletion blocked the deleterious effect of cocaine on SVZ cell proliferation in males. Cocaine‐exposed D1−/− males also had reduced neuronal phenotype of SVZ newborn cells and increased striatal neuronal maturity. D2−/− mice had lower proliferative and neural precursor responses. Cocaine in D2−/− females or coadministered with Raclopride in wild‐type females improved SVZ cell proliferation, an effect that positively correlated with plasma brain‐derived neurotrophic factor (BDNF) concentrations. In conclusion, the sex‐specific D1R and D2R signaling on SVZ cell proliferation, neural progenitor and neuronal maturity is differentially perturbed by cocaine, and BDNF may be required to link D2R to neuroplasticity in cocaine addiction in females.

Time’s Causal Power, 2021

Nutrients, 2021

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Mathematics, 2020

In this paper we obtain a novel implementation for irregular clouds of nodes of the meshless meth... more In this paper we obtain a novel implementation for irregular clouds of nodes of the meshless method called Generalized Finite Difference Method for solving the complex Ginzburg–Landau equation. We derive the explicit formulae for the spatial derivative and an explicit scheme by splitting the equation into a system of two parabolic PDEs. We prove the conditional convergence of the numerical scheme towards the continuous solution under certain assumptions. We obtain a second order approximation as it is clear from the numerical results. Finally, we provide several examples of its application over irregular domains in order to test the accuracy of the explicit scheme, as well as comparison with other numerical methods.

Palíndromo, 2013

Os games (jogos eletrônicos) são fenômeno marcante nos valores e hábitos da cultura atual, eviden... more Os games (jogos eletrônicos) são fenômeno marcante nos valores e hábitos da cultura atual, evidenciando a importância do jogo para a humanidade. Eles são objeto de fundamentação interdisciplinar, demandam diálogo entre profissionais de áreas diversas. Por isso, o projeto “Diálogos entre Arte e Design” (UDESC/CNPq, 2012-2013) foi proposto por seis pesquisadores de games educativos e/ou artísticos. O diálogo é norteado pelo game A mansão de Quelícera, resultado e objeto de pesquisas acadêmicas que tanto destacaram as qualidades do jogo quanto apontaram melhorias possíveis. Este artigo apresenta o ponto de partida do “Diálogos entre Arte e Design”, o qual tem por objetivo: a) aproximar conceitos e métodos usados no desenvolvimento e na avaliação de games educativos; b) produzir versão revisada de A mansão de Quelícera, a ser disponibilizada gratuitamente na web a partir de 2013.